Vacuum pumpout and pressure relief valve

ABSTRACT

A relief valve assembly is part of a removable poppet kit which includes special mounting and removing tools. A removable-poppet assembly is compatible with a conventional operator and comprises a poppet and a Z-bar biased toward one another by a spring along a plunger. The removable-poppet assembly is mounted on a valve housing by clamping an axial shoulder of the valve housing between the poppet and the Z-bar. The tools include means for manually separating the poppet from the Z-bar, and a T-shaped tool for holding the poppet and Z-bar in a separated configuration so that the removable-poppet assembly can be removed or mounted.

United States Patent Draper et al.

VACUUM PUMPOUT AND PRESSURE RELIEF VALVE Inventors: James W. Draper,Morro Bay; Lowell N. Edwards, Los Osos, both of Calif.

Assignee: Cryogenic Engineering Company,

Denver, Colo.

Filed: Feb. 25, 1971 App1.No.: 118,813

US. Cl. ..137/315, 137/541, 220/25, 251/291 Int. Cl ..Fl6k 43/00 FieldofSearch ..137/315,316,329,329.01, 329.04, 137/541, 542, 543.13, 543.15;220/25; 251/291, 318, 321

References Cited UNITED STATES PATENTS 3,013,579 12/1961 Gilliam ..137s41 x 3,302,661 2/1967 Williams ..251/291 x FOREIGN PATENTS ORAPPLICATIONS 491,332 1 1919 France .Q ..220/25 Primary Examiner--MartinP. Schwadron Assistant Examiner-David R. Matthews Attorney-Griffin,Branigan & Kindness [57] ABSTRACT A relief valve assembly is part of aremovable poppet kit which includes special mounting and removing tools.A removable-poppet assembly is compatible with a conventional operatorand comprises a poppet and a Z-bar biased toward one another by a springalong a plunger. The removable-poppet assembly is mounted on a valvehousing by clamping an axial shoulder of the valve housing between thepoppet and the Z-bar. The tools include means for manually separatingthe poppet from the Z-bar, and a T-shaped tool for holding the poppetand Z-bar in a separated configuration so that the removable-poppetassembly can be removed or mounted.

19 Claims, 5 Drawing Figures PATENTEUHAR 6M 3,119,200

flo INVENTORS g l4 MS W. DRAPER LUNELL N. EDWARDS BY o ,hu qm TTORNEYSVACUUM PUMPOUT AND PRESSURE RELIEF VALVE BACKGROUND OF THE INVENTIONThis invention relates generally to the art of relief valves and moreparticularly to relief valves having removable poppet assemblies.

A vacuum insulated storage vessel or transfer line normally includes aninner wall and an outer envelope, or container, forming an insulatingvacuum space therebetween. A valve opening connecting the vacuum spacewith outside atmosphere is often provided for evacuating the vacuumspace and relieving overpressures in the vacuum space when there is aleak in the inner wall. A valve which controls fluid flow through thevalve opening must be compatible with a valve operator", which holds thevalve in a throat open configuration during pumpdown of thevacuum-space. Further, such a valve must provide a fast response inorder to relieve even slight overpressures in the vacuum space.Consequently, it is an object of this invention to provide an improvedpressure relief valve which is compatible with a simple valve operatorfor opening the valve during pumpdown of the vacuum space and which alsohas a fast response to relieve overpressures in the vacuum space toprevent rupture of the evacuated structure s walls.

A safety relief valve often comprises a valve housing and a poppetassembly. The valve housing is attached to a chamber-such as on theouter envelope of a vacuum space-and forms a conduit along which fluidflows into or out of the chamber. The poppet valve assembly includes avalve poppet which is biased to close off the chamber so that fluidflows through the housing only when fluid pressure force in the chamberovercomes the poppet biasing force.

Normally, the outer envelope, or container, and a valve housing aremanufactured separately and then the valve housing is welded onto thecontainer. In some prior art safety relief valves the poppet assembliesand valve housings are manufactured as units so that they are notreadily separable from one another. In such cases the poppet assembliesare mounted on the valve housing when the valve housing is welded to thecontainer. This is not desirable because poppet assemblies often containheat sensitive elements such as springs and O-rings which can be damagedduring the welding process.

Further, it is often desirable to replace seals and springs in poppetassemblies; and this is difficult to do when the poppet assemblies andvalve housings are not readily separable.

Hence, other objects of this invention are to provide a safety reliefvalve kit including a poppet assembly which may be readily separatedfrom a valve housing and special tools to aid in the mounting anddismounting of the poppet assembly on a valve housing.

Some prior art safety relief valves comprise poppet assemblies which arethreadably mounted on valve housings. A significant shortcoming of suchsafety relief valves is that forming threads on the housings and thepoppet assemblies increases manufacturing costs. It is therefore anotherobject of this invention to provide a threadless safety relief valvewhich provides less expensive means for attaching a poppet assembly to avalve housing.

SUMMARY OF THE INVENTION According to principles of this invention, avalve housing has an axially protruding shoulder at its outer end whichforms a nozzle opening. A biasing spring biases the poppet downwardlyagainst the outer end of the valve housing and biases a Z-bar upwardlytowards the poppet against an inner side of the shoulder, therebyclamping the shoulder between the poppet and the Z-bar. To remove thepoppet assembly from the valve housing a special handle is attached tothe poppet, and the poppet is lifted manually. A T-shaped tool isinserted between the poppet and the Z-bar, thereby holding themseparated. The poppet assembly is then rotated at an angle with thehousing so that one end of the Z-bar clears the shoulder and the poppetassembly is removed.- To insert the poppet assembly a tool plate is usedto restrain the Z-bar as the Z-bar and poppet are manually separated andthe T-shaped tool is again inserted between the poppet and the Z-bar.The poppet assembly isthereafter installed in the valve housing in anopposite manner from that described above. The valve housing and poppetassembly of this invention are compatible with a conventional valveoperator; that is, the valve housing is of such a size and shape as tobe mated with the valve operator and the poppet assembly is attachableto an operator shaft of the valve operator."

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing and other objects,features and advantages of the invention will be apparent from thefollowing more particular description of the preferred embodiment of theinvention, as illustrated in the accompanying drawings in whichreference characters refer to the same parts throughout the differentviews. The drawings are not necessarily to scale, emphasis instead beingplaced upon illustrating the principles of the invention in a clearmanner.

FIG. 1 is a partially cutaway elevation of a removable-poppet kitemploying principles of this invention;

FIG. 2 is a partially cutaway elevation of a valve assembly employingprinciples of this invention wherein a T-shaped holding tool and ahandle are being used to aid in mounting a removable-poppet assembly ona valve housing;

FIG. 3 is a partially cutaway elevation of a valve assembly employingprinciples of this invention when a poppet assembly is fully installedon a valve housing;

FIG. 4 is a top view of a Z-bar, shown in FIGS. 1-3; and,

FIG. 5 is a partially cutaway elevation of a valve assembly employingprinciples of this invention with a valve operator also mounted thereon.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to FIGS. 1-4, thevalve assembly of this invention comprises a valve housing 10 and apoppet assembly 12. The valve housing 10 has a tubular shape and iswelded at its lower end to the outer wall 14 of a container such as theouter envelope of vacuum insulated transfer line. An inwardly protrudingfirst shoulder 16 is located at the upper end of a valve housing bore 13and forms a nozzle opening 18. A second shoulder 15 is located in thebore 13 adjacent to the first shoulder 16 and protruding to a lesserextent than the first shoulder 16. An O-ring 20 is mounted at the upperend of the valve housing 10.

The poppet assembly includes a poppet 22, a plunger 24, a Z-bar 26, avalve spring 28 and a spring retaining plate 30. In the illustratedembodiment, the plunger 24 is an integral part of the poppet 22 and actsto guide the poppet 22 as it opens and closes. The Z-bar 26 is slidablymounted on the plunger 24 and the spring retaining plate 30 is fixedlymounted at the lower end of the plunger 24, as seen in FIGS. 1 and 3.The valve spring 28 is also mounted on the plunger 24 and presses thespring retaining plate 30 and the Z-bar 26 away from one another; thus,the Z-bar 26 is biased toward the poppet 22.

The Z-bar 26 is rectangular in shape (see FIG. 4) but is bent so thatits center portion 32 is closer to the poppet 22 than its outer ends 34.

The removable-poppet assembly 12, described above, is part of aremovable poppet kit which also includes special tools for removing andmounting the removable poppet assembly. The tools, which are used tooperate the poppet assembly 12, are shown in FIGS. 1 and 2.

The first tool is an eye bolt or handle 38, having male threads at itsend which can be screwed into a threaded bore 36 in the poppet 22 toenable one to trip the poppet 22.

The second tool is a tool plate 40 which has an opening 42 therein. Thetool plate 40 is used to restrain the Z-bar 26 as the handle 38 is usedto pull the poppet 22 to an open position, as shown in FIG. 1.

The third tool is a T-shaped holding tool 44 which is used as a block tohold the Z-bar 26 and the poppet 22 in a separated configuration asshown in FIG. 2.

Referring now to FIG. 5, there is shown the valve housing and the poppetassembly 12 employed in conjunction with a valve operator 46. The valveoperator includes an operator housing 48, an operator handle 50, anoperator shaft 52 and an operator tube 53 for communicating with acavity 54.

The operator housing 48 forms the cavity 54 in which the valve housing10 snugly fits. The operator handle 50 is rotatably attached to theoperator shaft 52 at the top of the operator housing 48 and has anoperator handle cam 56 at one end thereof which presses against the topof the operator housing 48 as the handle is rotated. The operator shaft52 extends downwardly from the operator handle 50 and through theoperator housing 48, into the cavity 54 to engage the male threadslocated at the lower end of the operator shaft.

To install a removable-poppet assembly 12 on a valve housing 10 theZ-bar 26 is placed under the tool plate 40 (FIG. 1). The eye bolt 38 isthen screwed into the threaded bore 36 and used as a handle for manuallypulling the poppet 22 away from the Z-bar 26. Once the poppet 22 and theZ-bar 26 are separated the T- shaped holding tool 44 is inserted betweenthese two members thereby blocking the Z-bar from closing on the poppet22. In this configuration the poppet assembly 12 is rotated to an angleas shown in FIG. 2 and one of the outer ends 34 of the Z-bar 26 isinserted through the nozzle opening 18 below the second 6 shoulder 15.At this point, the opposite end 34 can also be pushed through the nozzleopening 18. The poppet assembly 12 is now rotated to a verticalposition, as seen in FIG. 2. In this position the outer ends 34 of theZ-bar 26 clear the second shoulder 15 but are prevented from passingthrough the nozzle opening 18 by the first shoulder 16. The T-shapedholding tool 44 is then removed from between the Z-bar 26 and the poppetassembly 12 and the valve spring 28 clamps these two members togetheragainst the first shoulder 16. Finally, the eye bolt 38 is screwed outof the threaded bore 36 and the safety relief valve appears as shown inFIG. 3.

To remove the poppet assembly 12 from the valve housing 10 the abovedescribed procedure is reversed; however, the tool plate 46 is notneeded.

The valve operator 46 shown in FIG. 5, is operated by pushing theoperator housing 48 down onto the valve housing 10 so the valve housing10 extends into the cavity 54 and forms a seal with operator housing 48.The male threads 58 of the operator shaft 52 are screwed into thethreaded bore 36 (not shown in FIG. 5 but see FIGS. 1 and 2).

To evacuate a container-for example, in order to create a vacuum spacein a cryogenic transfer linethe operator handle 50 is rotated aboutpoint 64 to a vertical position as shown in FIG. 5. In this manner cam56 presses against the top of the operator handle 48 and thereby pullsthe operator shaft 52 and the poppet 22 upwardly. Now the poppetassembly 12 is in a throat open position and fluid can be removed from,or inserted into the container 14 through the tube passage 60. To closethe valve poppet 22 the operator handle 50 is rotated to a horizontalposition.

It will be appreciated by those skilled in the art that the valveassembly described herein, including the valve housing and the poppetassembly with its associated tools, provide an uncomplicated mechanismfor removing and installing a poppet assembly in a valve housing. Inaddition, the poppet assembly 12, because of its uncomplicated design,provides accurate overpressure relief; the sensitivity thereof being afunction of the strength of the valve spring 28. Further, the valveassembly of this invention is compatible to a conventional valveoperator and is suitable for use with all types of evacuated devices.

It can be further appreciated by those skilled in the art, that theinvention disclosed herein has been particularly shown and describedwith reference to a preferred embodiment, however various changes inform and detail may be made therein without departing from the spiritand scope of the invention. For example, a cap" may be added to theremovable-poppet valve kit for protecting the poppet valve assembly 12when it is mounted on the valve housing 10.

The embodiments of the invention in which an exclusive property orprivilege are claimed are defined as follows:

1. A removablepoppet-assembly kit containing a poppet assembly of thetype that can be selectively mounted on, or removed from, a valvehousing, wherein said poppet assembly comprises:

a P pp a plunger means attached to said poppet for guiding the movementof said poppet;

a spring means having first and second endsand being mounted on saidplunger means for biasing said poppet toward a closed position;

a retaining means cooperating with said plunger for limiting movement ofsaid first end of said spring means relative to said plunger; and,

an assembly mounting means which is slidably mounted on said plunger forcooperating with said second end of said spring means to retain saidpoppet assembly on said valve housing, said assembly mounting meanshaving such a shape that a relatively flat center portion thereof iscloser to said poppet than outer extremities thereof.

2. A removable-poppet-assembly kit as claimed in claim 1 wherein isfurther included a blocking-tool means for blocking said assemblymounting means and said poppet apart from one another.

3. A removable-poppet-assembly kit as claimed in claim 2 wherein saidblocking tool comprises an elongated shaft having a laterally extendingflange at the end thereof.

4. A removable-poppet-assembly kit as claimed in claim 3 wherein isfurther included a handle, and said poppet includes a handle engagingmeans for engaging said handle.

5. A removable-poppet-assembly kit as claimed in claim 4 wherein saidhandle engaging means comprises a threaded bore and said handlecomprises a threaded shaft which is engageable with said threaded bore.

6. A removable-poppet-assembly kit as claimed in claim 4 wherein isfurther included a tool plate means for temporarily restraining saidassembly mounting means when said poppet is manually operated and saidpoppet assembly is not installed on said valve housing.

7. A removable-poppet-assembly kit as claimed in claim 6 wherein saidtool plate means has an opening therein which is smaller than the widthof said assembly mounting means.

8. A removable-poppet-assembly kit as claimed in claim 2 wherein isfurther included a handle and said poppet includes a handle engagingmeans for engaging said handle.

9. A removable-poppet-assembly kit as claimed in claim 8 wherein isfurther included a tool plate means for temporarily restraining saidassembly mounting means when said poppet is manually operated and saidpoppet assembly is not installed on said valve housing.

10. A removable-poppet-assembly kit as claimed in claim 2 wherein isfurther included a tool plate means for temporarily restraining saidassembly mounting means when said poppet is manually operated and saidpoppet assembly is not installed on said valve housing.

11. A removable-poppet-assembly kit containing a poppet assembly of thetype that can be selectively mounted on, or removed from, a valvehousing, wherein said poppet assembly comprises:

a poppet;

a plunger means attached to said poppet for guiding the movement of saidpoppet;

a spring means having first and second ends and being mounted on saidplunger means for biasing said poppet toward a closed position;

a retaining means cooperating with said plunger for limiting movement ofsaid first end of said spring means relative to said plunger;

an assembly mounting means for cooperating with said second end of saidspring means to retain said oppet assembly on said valve housing; and, alocking-tool means for blocking said assembly mounting means and saidpoppet apart from one another.

12. A removable-poppet-assembly kit as claimed in claim 11 wherein saidblocking tool comprises an elongated shaft having a laterally extendingflange at the end thereof.

13. A removable-poppet-assembly kit as claimed in claim 12 wherein isfurther included a tool plate means for temporarily restraining saidassembly mounting means when said poppet is manually operated and saidpoppet assembly is not installed on said valve housing.

14. A removable-poppet-assembly kit as claimed in claim 13 wherein saidtool plate means has an opening therein which is smaller than the widthof said assembly mounting means.

15. A removable-poppet-assembly kit as claimed in claim 14 wherein isfurther included a handle and said poppet includes a handle engagingmeans for engaging said handle.

16. A removable-poppet-assembly kit as claimed in claim 15 wherein saidhandle engaging means comprises a threaded bore and said handlecomprises a threaded shaft which is engageable with said threaded bore.

17. A removable-poppet-assembly kit as claimed in claim 12 wherein isfurther included a handle and said poppet includes a handle engagingmeans for engaging said handle.

18. A removable-p0ppet-assembly kit as claimed in claim 17 wherein saidhandle engaging means comprises a threaded bore and said handlecomprises a threaded shaft which is engageable with said threaded bore.

19. A method of installing a poppet assembly of the type which includesa poppet and an assembly mounting means biased toward said poppet onto avalve housing of the type having an axially protruding shoulder forminga valve nozzle opening, said method comprising the steps of:

pulling said assembly mounting means apart from said poppet;

inserting a blocking means between said poppet and said assemblymounting means thereby holding them apart in a semipermanent manner;

rotating said blocked poppet assembly at an angle relative to said valvehousing;

inserting one end of said assembly mounting means below said shoulder;

rotating said blocked poppet assembly to a straight position relative tosaid valve housing; and, removing said blocking means from between saidpoppet and said assembly mounting means.

1. A removable-poppet-assembly kit containing a poppet assembly of thetype that can be selectively mounted on, or removed from, a valvehousing, wherein said poppet assembly comprises: a poppet; a plungermeans attached to said poppet for guiding the movement of said poppet; aspring means having first and second ends and being mounted on saidplunger means for biasing said poppet toward a closed position; aretaining means cooperating with said plunger for limiting movement ofsaid first end of said spring means relative to said plunger; and, anassembly mounting means which is slidably mounted on said plunger forcooperating with said second end of said spring means to retain saidpoppet assembly on said valve housing, said assembly mounting meanshaving such a shape that a relatively flat center portion thereof iscloser to said poppet than outer extremities thereof.
 1. Aremovable-poppet-assembly kit containing a poppet assembly of the typethat can be selectively mounted on, or removed from, a valve housing,wherein said poppet assembly comprises: a poppet; a plunger meansattached to said poppet for guiding the movement of said poppet; aspring means having first and second ends and being mounted on saidplunger means for biasing said poppet toward a closed position; aretaining means cooperating with said plunger for limiting movement ofsaid first end of said spring means relative to said plunger; and, anassembly mounting means which is slidably mounted on said plunger forcooperating with said second end of said spring means to retain saidpoppet assembly on said valve housing, said assembly mounting meanshaving such a shape that a relatively flat center portion thereof iscloser to said poppet than outer extremities thereof.
 2. Aremovable-poppet-assembly kit as claimed in claim 1 wherein is furtherincluded a blocking-tool means for blocking said assembly mounting meansand said poppet apart from one another.
 3. A removable-poppet-assemblykit as claimed in claim 2 wherein said blocking tool comprises anelongated shaft having a laterally extending flange at the end thereof.4. A removable-poppet-assembly kit as claimed in claim 3 wherein isfurther included a handle, and said poppet includes a handle engagingmeans for engaging said handle.
 5. A removable-poppet-assembly kit asclaimed in claim 4 wherein said handle engaging means comprises athreaded bore and said handle comprises a threaded shaft which isengageable with said threaded bore.
 6. A removable-poppet-assembly kitas claimed in claim 4 wherein is further included a tool plate means fortemporarily restraining said assembly mounting means when said poppet ismanually operated and said poppet assembly is not installed on saidvalve housing.
 7. A removable-poppet-assembly kit as claimed in claim 6wherein said tool plate means has an openIng therein which is smallerthan the width of said assembly mounting means.
 8. Aremovable-poppet-assembly kit as claimed in claim 2 wherein is furtherincluded a handle and said poppet includes a handle engaging means forengaging said handle.
 9. A removable-poppet-assembly kit as claimed inclaim 8 wherein is further included a tool plate means for temporarilyrestraining said assembly mounting means when said poppet is manuallyoperated and said poppet assembly is not installed on said valvehousing.
 10. A removable-poppet-assembly kit as claimed in claim 2wherein is further included a tool plate means for temporarilyrestraining said assembly mounting means when said poppet is manuallyoperated and said poppet assembly is not installed on said valvehousing.
 11. A removable-poppet-assembly kit containing a poppetassembly of the type that can be selectively mounted on, or removedfrom, a valve housing, wherein said poppet assembly comprises: a poppet;a plunger means attached to said poppet for guiding the movement of saidpoppet; a spring means having first and second ends and being mounted onsaid plunger means for biasing said poppet toward a closed position; aretaining means cooperating with said plunger for limiting movement ofsaid first end of said spring means relative to said plunger; anassembly mounting means for cooperating with said second end of saidspring means to retain said poppet assembly on said valve housing; and,a blocking-tool means for blocking said assembly mounting means and saidpoppet apart from one another.
 12. A removable-poppet-assembly kit asclaimed in claim 11 wherein said blocking tool comprises an elongatedshaft having a laterally extending flange at the end thereof.
 13. Aremovable-poppet-assembly kit as claimed in claim 12 wherein is furtherincluded a tool plate means for temporarily restraining said assemblymounting means when said poppet is manually operated and said poppetassembly is not installed on said valve housing.
 14. Aremovable-poppet-assembly kit as claimed in claim 13 wherein said toolplate means has an opening therein which is smaller than the width ofsaid assembly mounting means.
 15. A removable-poppet-assembly kit asclaimed in claim 14 wherein is further included a handle and said poppetincludes a handle engaging means for engaging said handle.
 16. Aremovable-poppet-assembly kit as claimed in claim 15 wherein said handleengaging means comprises a threaded bore and said handle comprises athreaded shaft which is engageable with said threaded bore.
 17. Aremovable-poppet-assembly kit as claimed in claim 12 wherein is furtherincluded a handle and said poppet includes a handle engaging means forengaging said handle.
 18. A removable-poppet-assembly kit as claimed inclaim 17 wherein said handle engaging means comprises a threaded boreand said handle comprises a threaded shaft which is engageable with saidthreaded bore.